What is the loudest electronic siren?

[siren fan]

I thought the loudest siren in production today was the Tempest 135?

[ver tum]

I thought the loudest siren in production today was the Tempest 135?

It is, but we're talking about electronic sirens, and the T-135 is an electro-mechanical siren, not an electronic one.

[siren fan]

Oh my bad.

[acoustics101]

The best answer is to go straight to the source. 129 dB at 100 feet is the highest rating that I can find.
http://www.whelen.com/outdoor/index.htm
More importantly than the dB rating is the frequency range over which this output can be maintained.

Currently the loudest electronic siren is the Whelen WPS-4004 and Vortex R-4. The loudest ever made would likely be the Whelen WPS-4008.

Some will argue that the loudest electronis siren ever made was the EOWS 812 with a 132db output at 100ft., but the catalog that that came from had a bunch of other screwed up output ratings like 128dB for a TBeam and 131dB for a TBolt.

What are the real DB ratings for those Whelens, and for the EOWS812?

[SirenMadness]

I really wonder as to why people like to refer to speaker sirens as electronic sirens. Yes, speaker sirens are all electronic, but so are most of the mechanical sirens produced these days. A T-128 is electronic... a 2001 SRN is electronic... a Sentry siren is electronic, as well. "Wait, only the control boxes are electronic!" Yeah, but when you look at a speaker siren, most of the time, all you're going to see is a speaker driver or a group of them, if not a rotational motor as well; rarely any electronics up there. All of the sound-cards, amps, sensors and other devices are located in the control boxes. I do consider the control boxes to be part of the siren they power and direct, so exclusively giving the title of "electronic" to a speaker siren sounds a bit vague! I'm not trying to derail this thread, but this seems like a pretty interesting point!

Anyway, the loudest speaker siren currently made today, based on my knowledge, is the WPS 2910, as it delivers its powerful sound in all directions at the same time. However, when you think about all of the possible quantities and arrangements of speakers for an ELS siren, you might as well have a winner there, even though I don't know of any such large arrangements and sizes of this type of siren existing.

[StonedChipmunk]

I really wonder as to why people like to refer to speaker sirens as electronic sirens. Yes, speaker sirens are all electronic, but so are most of the mechanical sirens produced these days. A T-128 is electronic... a 2001 SRN is electronic... a Sentry siren is electronic, as well. "Wait, only the control boxes are electronic!" Yeah, but when you look at a speaker siren, most of the time, all you're going to see is a speaker driver or a group of them, if not a rotational motor as well; rarely any electronics up there. All of the sound-cards, amps, sensors and other devices are located in the control boxes. I do consider the control boxes to be part of the siren they power and direct, so exclusively giving the title of "electronic" to a speaker siren sounds a bit vague! I'm not trying to derail this thread, but this seems like a pretty interesting point!

To be frank, it is because electronic sirens produce an electronic tone, mechanical (hand-crank) sirens produce a mechanical tone, and electro-mechanical sirens produce a mechanical tone using electricity.



EDIT: Direct from the Whelen site, the ANSI definitions are:

Electronic Siren: A siren that produces tonal sounds by amplifying the output of an electronic signal generator and broadcasting the amplified signal from one or more electrodynamic loudspeakers.

Mechanical Siren: A siren that produces tonal sounds by periodically interrupting a flow of compressed air. Mechanical sirens may be motor or engine driven, and the air compressor may be integral with or separate from the flow interrupter.

Mechanical/Electronic Siren: A siren that uses a tone generator driven by mechanical means, and the tone generator output is applied by direct connection to loudspeakers, or through one or more electronic amplifiers to loudspeakers.

Apparently "electromechanical" sirens are still defined as mechanical.

[SirenMadness]

Maybe the term is here to stay, but it is not as credible as saying "speaker siren" in my opinion. I guess you can't really argue with ANSI, but that's the way I view the definition of a siren like a Whelen.

[StonedChipmunk]

Maybe the term is here to stay, but it is not as credible as saying "speaker siren" in my opinion. I guess you can't really argue with ANSI, but that's the way I view the definition of a siren like a Whelen.

Why call it a "speaker siren" then? Just call it a (loud)speaker.

Thing is you can't call a Thunderbolt an electronic siren. "Electronic" usually means something run purely by electricity, like a flashlight or alarm clock.

Ah, but wait a second. Don't speakers run using mechanical means? The magnet causes it to vibrate and produce a tone, correct? So it must be mechanical!

Wait a second. Who divided by zero?

[SirenMadness]

True, the speakers themselves aren't electronic; their amp(s) are, though.

Why call it a "speaker siren" then? Just call it a (loud)speaker.

That's the point; people may call it whatever they feel describes it the best sometimes, as long as others still understand you, but it isn't as if exactly all of the other terms out there are completely descriptive of what they cover in their meaning, though I'm too lazy to think of any now.

Also, I had this idea of an electronic siren like a Modulator, only all of the sound is concentrated from the horizontal drivers down a shaft and through an output manifold at the bottom; this may distort voice by a certain degree, but it might be very loud.

[acoustics101]

Good point! I call any siren based on a chopper a mechanical siren. The Thunderbolt is certainly one of these. Speaker sirens all use electronics to drive them, so it's really all down to a matter of semantics as to whether you want to call it an electronic siren or speaker siren. The acoustical output of a speaker siren is limited to the speaker efficiency (30% is considered high) times the amplifier power in watts.

One example of an electromechanical siren would be one that uses a voice coil driven valve to modulate a flow of air to a horn (a modulated air loudspeaker). You could think of such a device as a voice coil driven diaphone. The output of such a device depends somewhat on the amplifier power, but mostly on the power in the air stream, just as in a mechanical siren.

The Wyle Laboratories WAS3000 uses a voice coil driving a slotted cylinder. Air enters through the moving slots in the voice coil and exits through stationary slots to the throat of a horn. NASA uses these for acoustical stress testing of spacecraft components.

Such a device would have the advantage of making voice capability (albeit low quality) possible, along with the acoustical power of a mechanical motor driven siren, such as the Chrysler.

Thing is you can't call a Thunderbolt an electronic siren. "Electronic" usually means something run purely by electricity, like a flashlight or alarm clock.

Ah, but wait a second. Don't speakers run using mechanical means? The magnet causes it to vibrate and produce a tone, correct? So it must be mechanical!